This is a classic challenge that gets you thinking about shapes and structures. It is easy to organise and really fun.
In a team, make the tallest tower you can using only the materials listed below, in 30 minutes.
1 packet of regular uncooked spaghetti
20 small marshmallows
The team whose tower lasts through the entire judging period and is the tallest (measured from the ground to the highest point of the tower) is the winner.